How to not insert a blank value into the database

[wesman2232]

<?php
       $clanname = anti_injection($_POST['clanname']);
       $getclanstats = mssql_query("SELECT EmblemUrl FROM Clan WHERE Name = '$clanname'");
       $getx = mssql_fetch_assoc($getclanstats);
    if(anti_injection($_POST['emblem']) == "")
    {
        $emblem = $getx['EmblemUrl'];
    }
    elseif($getx['EmblemUrl'] == "NULL")
    {
        $emblem = "NULL";
    }
    else
    {
        $emblem = anti_injection($_POST['emblem']);
    }
?>

How do I get this to not insert a blank value into the database if the value in there is NULL when the user input is blank, as to not change it?

[MentaL]

[Linear88]

Not sure how you're using $emblem:

<?php
    $clanName = anti_injection($_POST['clanname']);
    $clanQuery = mssql_query("SELECT EmblemUrl FROM Clan WHERE Name = '$clanName'");
    $clanData = mssql_fetch_assoc($clanQuery);
    $emblemPost = anti_injection($_POST['emblem']);
    $emblemDB = null;
    
    if ($emblemPost == "" || $emblemPost == null)
        $emblemDB = $clanData['EmblemUrl'];
    if ($clanData['EmblemUrl'] == null || $clanData['EmblemUrl'] == "")
        $emblemDB = NULL;

    if ($emblemDB != null)
    {
        // use $emblemDB
    }
?>

It's been a long time since I've ever written PHP code for mssql queries..
So if there are any mistakes, feel free to correct me.

[wesman2232]

          <div class="adm_tit"><?php echo $admingmp['53']; ?></div>
      <form action="index.php?act=admin&amp;do=clans" method="post">
      <table width="350" align="center" height="60" border="0" style="font-weight:bold; color:#FF3300;">
       <tr><td><?php echo $admingmp['42'].' :'; ?></td><td><input type="text" name="clanname" class="tbl_colbor" /></td></tr>
       <tr><td><?php echo $admingmp['54'].' :'; ?></td><td><input type="text" name="wins" class="tbl_colbor" /></td></tr>
       <tr><td><?php echo $admingmp['55'].' :'; ?></td><td><input type="text" name="losses" class="tbl_colbor" /></td></tr>
       <tr><td><?php echo $admingmp['56'].' :'; ?></td><td><input type="text" name="draws" class="tbl_colbor" /></td></tr>
       <tr><td><?php echo $admingmp['57'].' :'; ?></td><td><input type="text" name="points" class="tbl_colbor" /></td></tr>
       <tr><td><?php echo $admingmp['179'].' :'; ?></td><td><input type="text" name="emblem" class="tbl_colbor" /></td></tr>
       <tr><td></td><td width="130" align="right"><input type="submit" name="changestats" value="<?php echo $admingmp['4']; ?>" /></td></tr>
      </table>
      </form>
      <div class="tbl_errmes">
      <?php
      if(isset($_POST['changestats'])){
       $clanname = anti_injection($_POST['clanname']);
       $getclanstats = mssql_query("SELECT Wins, Losses, Draws, Point, EmblemUrl FROM Clan WHERE Name = '$clanname'");
       $getx = mssql_fetch_assoc($getclanstats);
    if(anti_injection($_POST['wins']) == "")
    {
       $wins = $getx['Wins'];
    }
    else
    {
           $wins = anti_injection($_POST['wins']);
    }
            if(anti_injection($_POST['losses']) == "")
        {
           $losses = $getx['Losses'];
        }
        else
        {
           $losses = anti_injection($_POST['losses']);
        }
            if(anti_injection($_POST['draws']) == "")
            {
               $draws = $getx['Draws'];
            }
            else
            {
                   $draws = anti_injection($_POST['draws']);
            }
        if(anti_injection($_POST['points']) == "")
        {
           $points = $getx['Point'];
        }
        else
        {
               $points = anti_injection($_POST['points']);
        }
    if(anti_injection($_POST['emblem']) == "")
    {
       $emblem = $getx['EmblemUrl'];
    }
    elseif($getx['EmblemUrl'] == "NULL")
    {
       $emblem = "NULL";
    }
    else
    {
           $emblem = anti_injection($_POST['emblem']);
    }
        $sql = mssql_query("SELECT Name FROM Clan WHERE Name = '$clanname'");
        if(!$clanname){
         echo $admingmp['60'];
        }elseif(mssql_num_rows($sql)<>0){
        $sql2 = mssql_query("UPDATE Clan SET Point='$points', Wins='$wins', Losses='$losses', Draws='$draws', EmblemUrl='$emblem' WHERE Name='$clanname'");
         echo $admingmp['59'];
        }else{
          echo $admingmp['58'];
        }
      }
      ?>

Here's the full code for you.
This is what's happening:
When nothing is set in Emblem input, it takes whatever data that is already in the database and uses it in the update query as to not reset anything to 0.
Say I put nothing in the emblem input because I don't want to update it and the database value for Clan's EmblemUrl is NULL, it takes the NULL value, but sets it as a blank value when updating the row.

[Solaire]

Check if mssql_num_rows returns at least more than 1 row or verify whether $getx is false or not. If it's false, there's no returned row from previous query. Also, NULL values in the database equal the PHP null value, or at least MySQL did. "" is an empty string and is not the same as null.

[wesman2232]

Check if mssql_num_rows returns at least more than 1 row or verify whether $getx is false or not. If it's false, there's no returned row from previous query. Also, NULL values in the database equal the PHP null value, or at least MySQL did. "" is an empty string and is not the same as null.

Yeah. Let's say I don't have anything in the EmblemUrl for my clan in the DB because it isn't set, so the value is NULL.
I'm using this script to update some other parts of my clan (Wins, Losses, etc) but I don't want to update Emblem yet.
I use the script and set everything except Emblem. It works for everything I set, but Emblem is now instead of NULL, it is blank.

Should I set it to it's own individual if else statement? If $getx['EmblemUrl'] == NULL then $emblem = "NULL" else $emblem = $_POST['emblem'] ?

[Solaire]

Yeah. Let's say I don't have anything in the EmblemUrl for my clan in the DB because it isn't set, so the value is NULL.
I'm using this script to update some other parts of my clan (Wins, Losses, etc) but I don't want to update Emblem yet.
I use the script and set everything except Emblem. It works for everything I set, but Emblem is now instead of NULL, it is blank.

Should I set it to it's own individual if else statement? If $getx['EmblemUrl'] == NULL then $emblem = "NULL" else $emblem = $_POST['emblem'] ?

You should use something similar to this:

"UPDATE Clan SET EmblemURL = " . ($getx['EmblemUrl'] == null ? "NULL" : "'" . $_POST['emblem'] . "'") so it'll turn into either EmblemURL = NULL or EmblemURL = '(emblem url)'.

Also, maybe simply removing the EmblemURL from the query syntax when $getx['EmblemURL'] is null might work as well, dependant on how you want it.

[wesman2232]

You should use something similar to this:

"UPDATE Clan SET EmblemURL = " . ($getx['EmblemUrl'] == null ? "NULL" : "'" . $_POST['emblem'] . "'") so it'll turn into either EmblemURL = NULL or EmblemURL = '(emblem url)'.

Also, maybe simply removing the EmblemURL from the query syntax when $getx['EmblemURL'] is null might work as well, dependant on how you want it.

The latter would be the best way to go at it as so I don't complicate the problem any more.
And since I'm still learning as I go on PHP, what is the ? used for in the query?
" . ($getx['EmblemUrl'] == null ? "NULL" : "'" . $_POST['emblem'] . "'

[Dave]

The ? basically means "if true".
And the : means "else".

if($getx['EmblemUrl'] == null)
{
  return 'NULL';
}
else
{
  return "'" . $_POST['emblem'] . "'";
} 

PHP Shorthand If/Else Using Ternary Operators (?:)

[Vusion]

The latter would be the best way to go at it as so I don't complicate the problem any more.
And since I'm still learning as I go on PHP, what is the ? used for in the query?
" . ($getx['EmblemUrl'] == null ? "NULL" : "'" . $_POST['emblem'] . "'

It's a ternary operation, it has nothing to do with the query.

((condition) ? true : false)

Trying to understand what you're trying to do but;

<?php
$emblem = ((anti_injection($_POST['emblem'])) ? ", EmblemURL = '".$anti_injection($_POST['emblem'])."'" : "");
$sql2 = mssql_query("UPDATE Clan SET Point='$points', Wins='$wins', Losses='$losses', Draws='$draws' ".$emblem." WHERE Name='$clanname'");
?>

I'm aware of how messed up that is, but I have a bad headache.

[Solaire]

The ? basically means "if true".
And the : means "else".

if($getx['EmblemUrl'] == null)
{
  return 'NULL';
}
else
{
  return "'" . $_POST['emblem'] . "'";
} 

PHP Shorthand If/Else Using Ternary Operators (?:)

This, except it doesn't necessarily return the operands so you might as well do a statement or anything else.

As for your query, something like this would be best:
UPDATE Clan SET Points '$points' " . ($getx['EmblemUrl'] != null ? ", EmblemURL = '" . $_POST['emblem'] . "'" : ""), Wins = '$Wins', etc.

[wesman2232]

Thanks guys for the help. I got it working the way I wanted to last night by basically removing the update to EmblemUrl if the input is blank. I do like all the other answers, as I didn't know you could do it like that. I'll use this for future reference.